1. Field of the Invention
The present invention relates to a portable display device, and more particularly to a portable display device having improved durability with a transformed mold frame.
2. Description of the Related Art
Recently, several kinds of flat display devices have been developed, in which the weak points of Cathode Ray Tubes (CRTs), that is, the weight and the volume, have been reduced. Such flat display devices include Liquid Crystal Displays (LCDs), Field Emission Displays (FEDs), Plasma Display Panels (PDPs), and Light Emitting Displays, etc.
Liquid Crystal Displays are smaller and lighter and have a low power consumption, and are considered to be an alternative to overcome the weak points of CRTs. At present, the Liquid Crystal Display is mounted on portable devices, such as cellular phones and PDAs (Portable Digital Assistants) and so on and on monitors and TVs.
FIG. 1 is a schematic perspective view of a conventional portable display device. In FIG. 1, a dual display device, such as a cellular phone, includes at least one Liquid Crystal Display.
The conventional portable display device 50 includes a first display panel 5, a mold frame 10 receiving a back light assembly (not shown), etc., and at least one printed circuit board 20 mounted on a rear surface of a mold frame 10 and a second display panel 30 mounted on the printed circuit board 20.
The first display panel 5 is a Liquid Crystal Display panel having upper and lower substrates and having liquid crystal cells arranged in a matrix therebetween. A Thin Film Transistor (TFT) is included with each liquid crystal cell to shift video signals.
An integrated circuit (not shown) is arranged on one side of the first display panel 5, and data signals and scan signals are supplied from the integrated circuit. The first display panel 5 which received the data signals and scan signals, displays a picture image corresponding to the data signal and scan signal.
The back light assembly supplies the light to display the constant picture image on the first display panel 5. The back light assembly includes a light source (not shown). A mold frame 10 is included on the back light assembly, and the first display panel 5 and light source, etc., are fixed inside of the mold frame 10. Alignment tips 10a are formed on the right angle edges of the mold frame 10 to guide the position of the printed circuit board 20. The printed circuit board 20 receives drive signals from the drive circuit of the cellular phone (not shown).
The printed circuit board 20 includes a cellular phone connector 22. The cellular phone connector 22 interfaces with another connector which is coupled to the driving circuit of the cellular phone, and receives the driving signals from the driving circuit of the cellular phone.
The printed circuit board 20 which receives the driving signals produces multiple control signals corresponding to the driving signals.
The control signals produced in the printed circuit board 20 are supplied to the first display panel 5 and light source and so on, and provides the constant picture image on the first display panel 5
Grooves corresponding to the alignment tips 10a on the mold frame 10 are formed on the printed circuit board 20. The grooves on the printed circuit board 20 are formed on the rectangular edge of the printed circuit board 20 and the alignment tips 10a are projected about as high as the printed circuit board 20.
Likewise, if, the grooves on the printed circuit board 20 are located on the alignment tips 10a, the printed circuit board 20 and the mold frame 10 can be attached in an array.
The second display panel 30 is connected to the printed circuit board 20 on a rear surface of the printed circuit board 20 and displays a picture image. The second display panel 30 is either an Organic Light Emitting Display panel or a Liquid Crystal Display panel.
In accordance with the trends of minimization and slimming of the portable device, the total thickness of the display device is decreasing and protection elements which are not used to drive the display device have been being removed, which cause slimming of the portable display device as whole. However, the slimming weakens the durability of the portable display device and causes frequent faults and destruction thereof. Accordingly, a structural method to improve the durability without increasing the thickness of the portable display device has been sought.